This invention relates to containers for storing and transporting materials in bulk form which are commonly known as bulk bags.
Bulk bags are widely used today in storing and transporting bulk materials in granular and powder form and sometimes in liquid or slurry form. These bulk bags are usually made of flexible reticulated materials such as woven polypropylene which are capable of holding large, heavy quantities of materials, typically weighing a ton or so. Where the bulk material is liquid or needs to be protected from ambient moisture, the bag is lined with an impervious liner made also of a flexible material such as polyethylene or nylon. For storage compactness, bulk bags are normally square with a bottom, four continuous sides and usually a top. They commonly have a fill chute which extends centrally from their tops and a discharge chute which depends centrally from their bottoms.
Once filled, bulk bags are usually moved about by forklift trucks. For example, they are often moved from beneath a hopper where they are filled to a warehouse storage area and to and from shipping docks where they are loaded and unloaded onto trucks, trains and container ships. In order to be loaded onto the tines of a forklift truck their bottoms must be elevated a little from the floor upon which they are supported. Otherwise the tines would puncture the bags and create a spill. Thus heretofore they have been supported upon pallets.
Heretofore, the use of conventional pallets has been accepted as simply a necessity. These pallets are usually made of a wood frame with a flat top supported a few inches above a flat bottom by spaced ribs. In loading a bulk bag upon a forklift truck the truck tines are lowered and driven into a gap in the ribs of the pallet between the pallet top and bottom. The tines are then lifted, usually titled and the loaded truck driven to another location where the bag is unloaded.
The use of pallets is very expensive. They are usually hand made by sawing plywood and boards and nailing the pieces together to form an assembled pallet. They are usually stored in stacks. Being subjected to rough handling they are often broken in use and have to be repaired or replaced. The damaged pallets and their pieces must thus be gathered and discarded. Even when they are not damaged they must be stored when not in use.
It thus is seen that if a way were to be found to avoid the use of conventional wooden pallets for the handling of bulk bags, a definitive advance would be achieved. Accordingly it is to this end that the present invention is primarily directed.
Briefly described, a palletized container for bulk materials comprises a bulk bag having a flexible bottom and flexible sides. An inflatable stand is mounted to the bag bottom. The inflatable stand has two elongated channels spaced apart a distance to receive two tines of a forklift truck. Prior to and between uses the container may be compactly stored with its sides furled and its stand deflated. For use the stand is inflated and the sides unfurled as with lifting straps attached to their top corners.
In another form of the invention a palletized container for bulk materials comprises a bag made of reticulated material having a bottom and sides. Inflatable bladders are mounted to the bag bottom which bound two tine receiving channels spaced apart a distance to receive two spaced tines of a forklift truck. A discharge chute may depend from the center of the bag bottom into another channel bounded by two of the inflatable bladders. Sheets preferably cover the bottoms of the two tine receiving channels.